1. Field of the Invention
The subject application generally relates to a handheld device, and more particularly, to a handheld device where a planar antenna is integrated into a detachable element thereof.
2. Description of Related Art
Currently, the popular communication has been gradually progressed to wireless communication, wherein the wireless communication devices more and more tend to variety such as smart mobile phone, multimedia player, PDA (personal digital assistant) and aviation GPS (global positioning system), and the like. Various electronic apparatuses with wireless transmission function are getting improved towards the light-slim-short-small design principle so as to better adopt our daily lives. It should be noted that an antenna serves as an indispensable component for many wireless communication systems. In particular, the antenna is a major key component relating to the integrated performance of the wireless communication system.
Taking a mobile phone as an example, in order to make it more compact, a mobile phone usually employs a planar antenna, which is disposed in a housing or a cover thereof and therefore is easier to be affected by other components and sub-assemblies of the mobile phone. The affecting components include, for example, speaker), battery or connector. Certainly, the height required by clearance of the planar antenna is also one of the key factors; i.e., the higher the clearance, the better radiation performance of the planar antenna is.
However, the space of a mobile phone is limited where it is quite uneasy to increase the height/volume to the clearance of the mobile phone.
On the other hand, various countries in the world have their own and often different communication specifications, referring to the following table. In Europe, for example, the frequency band in the communication technical specification of the second generation mobile phone (2 G communication technical specification) is specified as 880-960 MHz and 1710-1880 MHz, while the frequency band in the communication technical specification of the third generation mobile phone (3 G communication technical specification) is specified as 1920-2170 MHz and 880-960 MHz. In United States, the frequency band in the 2 G communication technical specification is specified as 824-894 MHz, while the frequency band in the 3 G communication technical specification is specified as 1850-1990 MHz and 824-894 MHz.
TABLE 1The communication specifications of Europe and USA2G3GEurope9001800Band 1Band 8880-960 MHz1710-1880 MHz1920-2170 MHz880-960 MHzUSA8501900Band 2Band 5824-894 MHz1850-1990 MHz1850-1990 MHz824-894 MHz
The antennas of the mobile phones in various countries are designed according to the communication specifications thereof, so that a mobile phone in the European Standard used in USA has bad radiation performance. Similarly, a mobile phone in the USA Standard used in Europe has bad radiation performance as well. In order to solve the above-mentioned problem, a user usually needs to purchase different mobile phones suitable for different countries' specifications. It should be noted that the mobile phones of different countries have different operation interfaces and different operation manners, so that the user needs to learn the different operation interfaces and operation manners to adapt different mobile phones, which bring the user great inconvenience.